The present invention relates to a cosmetic composition and, more particularly, to a method of preparing an impact resistant solid cosmetic composition. This method involves compression molding, into a dish mold, powder materials which contain spherical powders of organopolysiloxane elastomer.
Conventionally, a spherical powder of an organopolysiloxane elastomer, having characteristic elasticity, has been developed as a powder for use in cosmetic compositions and has been incorporated into a variety of products. Such a powder exhibits favorable properties when incorporated into cosmetic compositions, i.e., the cosmetic composition containing such a powder exhibits good skin fittability and spreadability on the skin, imparts a light and smooth sensation when applied to the skin, has a soft-touch sensation, and does not irritate the skin (Japanese Patent Application Laid-Open (kokai) No. 2-243612 and Japanese Patent Publication (kokoku) Nos. 4-17162 and 4-66446).
However, when a spherical powder of organopolysiloxane elastomer is incorporated into a cosmetic composition in a large amount in order to fully realize favorable properties of the powder, the resultant solid cosmetic composition disadvantageously exhibits deteriorated strength against impact (hereinafter referred to as impact resistance).
In view of the foregoing, an object of the present invention is to provide a solid cosmetic composition having excellent strength against impact even when a spherical powder of organopolysiloxane elastomer is incorporated into the cosmetic composition in a large amount.
In order to overcome the drawbacks, the present inventors have conducted earnest studies on a spherical powder of organopolysiloxane elastomer, and have found that, among spherical powders of organopolysiloxane elastomer which have a mean particle size of 0.1-200 xcexcm, a spherical powder of organopolysiloxane elastomer having a JIS A hardness of 50-100 does not impair the impact strength of a solid cosmetic composition even when the powder is incorporated into the cosmetic composition in a large amount, and provides a solid cosmetic composition having an excellent impact strength. The inventors have also found that a solid cosmetic composition containing a spherical powder of organopolysiloxane elastomer having a JIS A hardness of 50-100 exhibits excellent retention on the skin during use (hereinafter called xe2x80x9ccosmetic retentionxe2x80x9d) and has properties conventionally considered favorable, e.g., exhibiting good skin fittability and spreadability on the skin; imparting a light and smooth sensation when applied by rubbing (hereinafter referred to as light and smooth application sensation); and imparting no strange sensation or irritation to the skin. The present invention has been accomplished based on these findings.
Accordingly, in one aspect of the present invention, there is provided a solid cosmetic composition containing a spherical powder of organopolysiloxane elastomer having a JIS A hardness of 50-100 that has a mean particle size of 0.1-200 xcexcm (hereinafter referred to as xe2x80x9cthe solid cosmetic composition of the present inventionxe2x80x9d).
Preferably, the solid cosmetic composition contains the spherical powder of organopolysiloxane elastomer in an amount of 0.1-50.0 wt. % based on the entirety of the composition.
Particularly preferably, the solid cosmetic composition contains the spherical powder of organopolysiloxane elastomer having a JIS A hardness of 50-80.
As used herein, the term xe2x80x9cmean particle sizexe2x80x9d refers to a value which. is obtained by measuring the diameters in a specific direction of particles under an optical microscope and dividing the sum of respective diameters of particles by the number of measured particles.
The term xe2x80x9cJIS A hardnessxe2x80x9d refers to a hardness measured according to JIS K 6301 by use of the JIS A hardness meter.
The term xe2x80x9csolid cosmetic compositionxe2x80x9d refers to a cosmetic composition which is solidified by compacting powder such as solid face powder, powdery foundation, two-way (i.e., usable with or without water) foundation, foundation usable with water, solid emulsified foundation, or solid cheek rouge.
In a first embodiment of the present invention concerning a method of producing an impact resistant solid cosmetic, a method is provided comprising compression molding into a dish mold powder materials comprising a spherical powder of organopolysiloxane elastomer having a JIS A hardness of 60-100, and a mean particle size of 0.1-200 mm, said elastomer constituting 0.1-50.0 wt % based on the entirety of the cosmetic.
In a second embodiment of the present invention concerning a method of producing an impact resistant solid cosmetic, a method is provided according to the first embodiment above, wherein the powder materials are compression molded at a pressure of between 200 kgf/cm2 and 300 kgf/cm2.
In a third embodiment of the present invention concerning a method of producing an impact resistant solid cosmetic, a method is provided according to the first embodiment above, wherein the powder materials are compression molded at a temperature of between 10xc2x0 C. and 30xc2x0 C.
In a fourth embodiment of the present invention concerning a method of producing an impact resistant solid cosmetic, a method is provided according to the first embodiment above, wherein the compacted powder materials in the compacted cosmetic constitute 70.0-99.0 wt %, based on the entirety of the cosmetic.
In a fifth embodiment of the present invention concerning a method of producing an impact resistant solid cosmetic, a method is provided according to the first embodiment above, wherein the impact resistant solid cosmetic further comprises an oily ingredient.
In a sixth embodiment of the present invention concerning a method of producing an impact resistant solid cosmetic, a method is provided according to the fifth embodiment above, wherein the amount of the oily ingredient is 1.0-30.0 wt %.
In a seventh embodiment of the present invention concerning a method of producing an impact resistant solid cosmetic, a method is provided according to the first embodiment above, wherein the organopolysiloxane elastomer has a JIS A hardness of 60-80.
In an eighth embodiment of the present invention concerning a method of producing an impact resistant solid cosmetic, a method is provided according to the first embodiment above, wherein the cosmetic is selected from the group consisting of face powder, powdery foundation, two way foundation, formulations usable with water, solid emulsified formulation, and cheek rouge.
In a ninth embodiment of the present invention concerning a method of producing an impact resistant solid cosmetic, a method is provided according to the first embodiment above, said method comprising compression molding into a dish mold a mixture comprising 70.0-99.0 wt % of said powder materials and 1.0-30.0 wt % of an oily ingredient, said powder materials comprising a spherical powder of organopolysiloxane elastomer having a JIS A hardness of 60-100, and a mean particle size of 0.1-200 mm, said elastomer constituting 0.1-50.0 wt % based on the entirety of the cosmetic.
In a tenth embodiment of the present invention concerning a method of producing an impact resistant solid cosmetic, a method is provided according to the ninth embodiment above, wherein the powder materials are compression molded at a pressure of between 200 kgf/cm2 and 300 kgf/cm2 at a temperature of between 10xc2x0 C. and 30xc2x0 C.
In an eleventh embodiment of the present invention concerning a method for producing an impact resistant solid cosmetic, a method is provided according to the ninth embodiment above, wherein the powder materials are compression molded at a pressure of between 200 kgf/cm2 and 300 kgf/cm2 at a temperature of between 10xc2x0 C. and 30xc2x0 C.
In an eleventh embodiment of the present invention concerning a method for producing an impact resistant solid cosmetic, a method is provided according to the first embodiment above, wherein the powder materials are compacted 1-3 times.
In a twelfth embodiment of the present invention concerning a method for producing an impact resistant solid cosmetic, a method is provided according to the eleventh embodiment above, wherein the powder materials are compacted at a temperature of about 20xc2x0 C.xc2x110xc2x0 C.
In a thirteenth embodiment of the present invention concerning a method for producing an impact resistant solid cosmetic, a method is provided according to the twelfth embodiment above, wherein the powder materials are compacted under a pressure of 200-300 kgf/cm2.
In a fourteenth embodiment of the present invention, an impact resistant solid cosmetic is provided which is produced by the method of the first embodiment above.
In a fifteenth embodiment of the present invention, an impact resistant solid cosmetic is provided which is produced by the method of the fifth embodiment above.
In a sixteenth embodiment of the present invention, an impact resistant solid cosmetic is provided which is produced by the method of the ninth embodiment above.
In a seventeenth embodiment of the present invention, an impact resistant solid cosmetic is provided which is produced by the method of the tenth embodiment above.
In an eighteenth embodiment of the present invention, an impact resistant solid cosmetic is provided which is produced by the method of the thirteenth embodiment above.
Modes for carrying out the present invention is described.
The spherical powder of organopolysiloxane elastomer which is incorporated into the solid cosmetic composition of the present invention is composed of an organopolysiloxane elastomer having a JIS A hardness of 50-100, preferably 50-80. When the JIS A hardness is less than 50, the solid cosmetic composition containing the powder disadvantageously has poor strength against impact, whereas when the hardness is in excess of 100, cosmetic retention is disadvantageously deteriorated.
The spherical powder of organopolysiloxane elastomer that is incorporated into the solid cosmetic composition of the present invention has a mean particle size of 0.1-200 xcexcm, preferably 0.5-20.0. When the particle size is less than 0.1 xcexcm, a smooth plication sensation disadvantageously disappears, whereas when the particle size is in excess of 200 xcexcm, the powder causes an unfavorable rough sensation when applied by rubbing.
The spherical powder of organopolysiloxane elastomer which is incorporated into the solid cosmetic composition of the present invention may be a perfectly spherical powder or an oblate spherical powder. However, a perfect spherical powder is more preferable in that the composition containing the powder imparts a more favorable smoother application sensation.
No particular limitation is imposed on the method for producing the spherical powder (having a mean particle size of 0.1-200 xcexcm) of organopolysiloxane elastomer having a JIS A hardness of 50-100, and the powder can generally be produced by use of a curable organopolysiloxane composition as a raw material. Examples of the curable organopolysiloxane composition include:
an addition-curable organopolysiloxane composition which is cured through addition reaction between a diorganopolysiloxane having a silicon-bonded hydrogen atom and an organopolysiloxane having a silicon-bonded lower alkenyl group such as a vinyl group conducted in the presence of a platinum catalyst;
a condensation-curable organopolysiloxane composition which is cured through dehydrogenation reaction between a diorganopolysiloxane having hydroxyl groups at both molecule ends and a diorganopolysiloxane having a silicon-bonded hydrogen atom conducted in the presence of an organotin compound;
a condensation-curable organopolysiloxane composition which is cured through condensation reaction, such as dehydration or removal of alcohol, oxime, amine, amide, carboxylic acid, ketone, etc., between a diorganopolysiloxane having hydroxyl groups at both molecule ends and hydrolyzable organosilanes conducted in the presence of an organotin compound or titanate;
a peroxide-curable organopolysiloxane composition which is cured by the application of heat in the presence of an organic peroxide catalyst; and
a high-energy-ray-curable organopolysiloxane composition which is cured through radiation of xcex3-rays, UV-rays, or an electron beam.
Among these curable organopolysiloxane compositions, an addition-curable organopolysiloxane composition is preferred, in view of a high curing rate and homogeneity in curing. A particularly preferable composition comprises (A) a diorganopolysiloxane having at least two silicon-bonded hydrogen atoms in the molecule; (B) an organopolysiloxane having at least two lower alkenyl groups in the molecule; and (C) a platinum catalyst.
An organic group other than a lower alkenyl group may also bond to a silicon atom in an organopolysiloxane or a diorganopolysiloxane serving as a predominant component of the above-mentioned curable organopolysiloxane composition, and examples of such an organic group include an alkyl group such as methyl, ethyl, propyl, butyl, or octyl; a substituted alkyl group such as 2-phenylethyl, 2-phenylpropyl, or 3,3,3-trifluoropropyl; an aryl group such as phenyl, tolyl, or xylyl; and a monovalent hydrocarbyl group having a substituent such as an epoxy, carboxylate, or mercapto group.
Several methods may be employed for producing the spherical powder (having a mean particle size of 0.1-200 xcexcm) of organopolysiloxane elastomer having a JIS A hardness of 50-100 from the above-mentioned curable organopolysiloxane composition. Examples of the methods include the following (1) to (4):
(1) a method which involves mixing an addition-curable, condensation-curable, or peroxide-curable organopolysiloxane composition with water in the presence of a surfactant such as a nonionic, anionic, cationic, or amphoteric surfactant; forming a homogeneous aqueous dispersion by use of an apparatus such as a homogenization mixer, a colloid mill, a homogenizer, or a propeller mixer; releasing the dispersion into hot water at 50xc2x0 C. or higher to thereby perform curing; and drying,
(2) a method which involves spraying an addition-curable, condensation-curable, or peroxide-curable organopolysiloxane composition directly into hot air-flow to thereby perform curing,
(3) a method which involves spraying a high-energy-ray-curable organopolysiloxane composition under exposure to high-energy rays to thereby perform curing, and
(4) a method which involves curing an addition-curable, condensation-curable, peroxide-curable, or high-energy-ray-curable organopolysiloxane composition and crushing the cured product by use of a known crushing apparatus such as a ball mill, an atomizer, a kneader, or a roll mill.
Of these, the method (1) is preferred in that a powder having a more spherical particle shape and a small variation in particle size can be produced.
A spherical powder of organopolysiloxane elastomer is described in detail in Japanese Patent Application Laid-Open (kokai) No. 2-243612 and Japanese Patent Publication (kokoku) Nos. 4-17162 and 4-66446. Commercial products may be incorporated into the solid cosmetic composition of the present invention, and examples of such products include Trefil E-505 and Trefil E-506C (products of Dow Corning Toray Silicone Co., Ltd.).
The solid cosmetic composition of the present invention contains the above-described spherical powder of organopolysiloxane elastomer in an amount of preferably 0.1-50.0 wt. % based on the entirety of the composition, particularly preferably 1.0-20.0 wt. %. When the content is less than 0.1 wt. %, an intended effect on improvement in use-related characteristics provided through incorporation of a spherical powder of organopolysiloxane elastomer, such as imparting a light and smooth application sensation, is poor, whereas when the content is in excess of 50.0 wt. %, the resultant solid cosmetic composition has poor strength against impact; disadvantageously exhibits sluggish spreadability on the skin; and imparts a rough sensation.
In addition to the above-described spherical powder of organopolysiloxane elastomer, a pigment powder may be incorporated into the solid cosmetic composition of the present invention. No particular limitation is imposed on the pigment powder so long as it is one that is typically incorporated into a cosmetic composition, and any pigment powder such as an inorganic pigment powder or an organic pigment powder may be incorporated.
Example of the inorganic pigments include talc, kaolin, calcium carbonate, zinc flower, titanium dioxide, red iron oxide, yellow iron oxide, black iron oxide, ultramarine, titanium-coated mica, bismuth oxychloride, a binderg pigment, ultramarine pink, hydrated chromium oxide, titanated mica, chromium oxide, cobalt aluminum oxide, iron blue, carbon black, silicic anhydride, magnesium silicate, bentonite, mica, sericite, zirconium oxide, magnesium oxide, zinc oxide, titanium oxide, precipitated calcium carbonate, heavy calcium carbonate, light magnesium carbonate, heavy magnesium carbonate, and calamine.
Examples of the organic pigments include polyester, polymethylmethacrylate, cellulose, Nylon-12, Nylon-6, styrene-acrylic acid copolymers, polypropylene, poly(vinyl chloride), nylon powder, polyethylene powder, benzoguanamine powder, tetrafluoroethylene powder, boron nitride, fish scale flake, lake tar pigments, lake natural pigments, and inorganic-organic hybrid pigments.
Preferably, the pigment powder is hydrophobicized. No particular limitation is imposed on the hydrophobicized pigment powder so long as the powder has a hydrophobic surface. Examples of such powders include a pigment powder surface-treated with high-viscosity silicone; a pigment powder coated with a silicone resin which has been preliminary reacted with alkyl hydrogen polysiloxane; silicone-coated powder further treated with alkene; a pigment powder treated with one or more surfactants selected from a cationic surfactant, an anionic surfactant, and a nonionic surfactant; a wax-coated pigment powder; a pigment powder treated with dextrinized fatty acid; and a pigment powder treated with a fluorine compound containing a perfluoroalkyl group.
The solid cosmetic composition of the present invention preferably contains powders including the above-described spherical powder of organopolysiloxane elastomer in an amount of 70.0-99.0 wt. % based on the entirety of the composition.
In addition to powders including the above-described spherical powder of organopolysiloxane elastomer, one or more ingredients which are typically added to a solid cosmetic composition, such as an oily ingredient or water, may be incorporated into the solid cosmetic composition of the present invention without impairing the effects of the present invention.
Examples of the oily ingredient which is incorporated into the solid cosmetic composition of the present invention include:
silicone oils such as dimethylpolysiloxane, dimethylcyclopolysiloxane, methylphenyl polysiloxane, methyl hydrogen polysiloxane, higher fatty acid-modified organopolysiloxane, higher alcohol-modified organopolysiloxane, trimethylsiloxysilicate, and decamethylcyclopentanesiloxane;
hydrocarbon oils such as liquid paraffin, squalane, vaseline, polyisobutylene, and microcrystalline wax;
ester oils such as isopropyl myristate, myristyl octyldodecanol, and di(2-ethylhexyl) succinate;
glycerides such as neopentyl glycol diisooctanoate, glyceryl monostearate, triglyceryl monoisostearate, and triglyceryl cocoate;
oils and fats such as castor oil and olive oil;
lower alcohols such as ethanol;
higher alcohols such as octyldodecanol, hexadecyl alcohol, cetyl alcohol, oleyl alcohol, stearyl alcohol, and polyethylene glycol;
higher fatty acids such as lauric acid, palmitic acid, oleic acid, stearic acid, and isostearic acid;
waxes such as lanolin and beeswax; and
fluorocarbon oils.
Such oily ingredients are preferably incorporated in an amount of 1.0-30.0 wt. % based on the entirety of the composition.
When the solid cosmetic composition of the present invention is emulsified, the water content of the composition is typically 1.0-50.0 wt. % based on the entirety of the composition.
Other additives may also be incorporated into the solid cosmetic composition of the present invention, so long as the effects of the present invention are not impaired.
Examples of such additives include
humectants such as polyhydric alcohol (e.g., glycerin), mucopolysaccharides (e.g., sodium hyaluronate), and organic acids and salts thereof (e.g., amino acids, amino acid salts, and hydroxy acid salts);
surfactants such as cationic surfactants, anionic surfactants, and nonionic surfactants;
pharmaceuticals such as vitamin E and vitamin E acetate;
astringents; antioxidants; preservatives; perfume; pH regulators such as sodium secondary phosphate; clay minerals; thickeners; and ultraviolet absorbents.
Of these, a humectant is preferably incorporated into the composition in order to prevent evaporation of water from the solid cosmetic composition per se.
The solid cosmetic composition of the present invention may be employed as foundation, face powder, cheek rouge, eye-shadow, eyebrow pencils, and eye-liner.
Specific formulations of the solid cosmetic composition of the present invention are described below.